Runway incursions continue to threaten aviation safety during ground operations. A runway incursion is any unauthorized intrusion onto a runway, regardless of whether or not an aircraft presents a potential conflict. Airport signs and taxiway markings are designed to provide pilots with awareness to prevent such events from occurring; however, human errors due to poor visibility, fatigue, lack of position awareness, misunderstood air traffic control (ATC) clearances, or inadvertent flight-deck distractions still occur. In some cases this has led to inappropriate runway entry by the aircraft. Honeywell® has attempted to augment the pilots' positional awareness at the airport by developing airport moving maps (AMM) that provides both two- and three-dimensional views of the airport environment, commonly known as 2D AMM and 3D AMM.
Hold-position markings painted on airport surfaces indicate locations where an airplane is required to stop. Hold-position markings are used in three instances: 1) taxiways, 2) runways, and 3) runway approach areas. When used on taxiways, the markings identify the location for an airplane to stop if it does not have clearance to proceed onto a runway, at a controlled airport, or does not have adequate separation from traffic, at an uncontrolled airport. Hold lines may also be used on the taxiway to control traffic through taxiway intersections and instrument-landing system/microwave-landing system (ILS/MLS) critical areas. On runways, the markings are used for land and hold-short operations (LAHSO). Hold-position markings are also used at airports where the taxiway is located in the approach or departure area of a runway.
The virtual airport environments depicted in 2D AMM and 3D AMM affords the opportunity to augment the pilots' positional awareness by providing additional information and cues that do not exist in the real world. The virtual hold gate is one such example. The virtual hold gate replicates the hold lines seen on the airport runway or taxiway surface (see FIG. 1) in the 3D AMM environment. In the existing design, depiction of the virtual hold gate is rotated 90 degrees to the plane of the airport surface, in order to appear as a barrier blocking the path of the airplane. Activation of the existing animation is determined by the aircraft's proximity to the associated hold-short line and the aircraft's heading, relative to the location of the associated hold-short line. The virtual hold gate fades in as the aircraft approaches the hold-short line. The virtual hold gate fades out as the aircraft slows down to zero ground speed, prior to crossing the hold-short line.